Method for introducing into packages of all types, binding agents for undesired substances which detrimentally influence the packed material



INTO PACKAGES OF ALL TYPES, BINDING D SUBSTANCES WHICH DETRIMENTALLY L A I R E T3 A6 m R w E I K0 D 2 P. A Bw B HN d U E6 ECl RN NIEF SU MEL DF w m M U 1 m F RS WT W WG A T E M Dec. 10, 1968 FIG.

FIG. 3

FIG. 2

United States Patent 0 8 Claims. of. 156-276) ABSTRACT OF THE DISCLOSURE A method of making packaging material by applying an absorbing agent to an outer layer of thermoplastic material and superimposing an inner layer of thermoplastic material onto the absorbing agent and outer layer with the inner layer being permeable so that undesired substances in the contents of a package may be absorbed without diminishing the filling space of the package.

The present invention relates to the wrapping and packaging art and more particularly, to a method of making sealed packages which are provided with agents to protect the packaged material.

It is known in the prior art to add certain binding or absorbing agents to sealed packages, which depending on the nature and character of the material in the package, are intended to remove undesired moisture, oxygen or other gases which are detrimental to the material in the package or to the package itself. Thus the binding agents are utilized to protect the packaged material or the package as a whole from spoilage or damage.

These absorbing agents are either added directly to the packaged material, or are disposed in small containers of packaging material which are permeable to gas or moistu-re and then inserted into the main package. The small 0 container type have found particular application in the packaging of certain foodstuffs.

There are many disadvantages in the known methods of adding absorbing agents to packages, such as a greatly increased cost because of the need for special packaging and feeding devices required to perform this extra operation; in addition, the presence of a foreign body in the sealed package is undesirable in the case of foodstulfs from a spoilage viewpoint and is generally undesirable from a psychological viewpoint in being detrimental to 0 the sale of the product.

It is, therefore, an object of this invention to eliminate the above disadvantages in adding absorbing agents to a package.

Another object of this invention is to manufacture packaging material capable of absorbing undesired substances in the package without taking up any of the filling space of the package.

The present invention has another object in that an absorbing agent is dispersed between two layers of packaging material, one of which is permeable to the substance to be removed from the package.

In practicing the present invention, an absorbing agent is finely dispersed between adjacent surfaces of inner and outer layers of packaging material, and the inner layer of 65 packaging material is permeable to the undesirable substance which is to be removed.

Other objects and advantages of the present invention will become apparent from the following description taken in connection with the accompanying drawing wherein:

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FIGURE 1 is a partial perspective view of pack-aging material made according to the present. invention;

FIGURE 2 is a partial plan view of packaging material made according to a modification of the present invention;

FIGURE 3 is a cross section view taken along line 33 of FIGURE 2; and

FIGURE 4 is a partial perspective view of packaging material made according to another modification of the present invention.

As is illustrated in FIGURE 1, a packaging material, made according to the present invention, includes an inner layer 10, an outer layer 12 and an absorbing agent 14 therebetween. The inner layer 10 is made permeable to the deleterious material to be removed from the packaged material and forms the inside wall of the package while the outer layer 12 forms the outside wall.

From the foregoing it is apparent that the present invention is not limited to specific types of packaging material but can be used both in the manufacture of the socalled soft packages and in the manufacture of hard packages which wholly or partially consist of rigid packaging materials. The specific material of the layer or sheet forming the inside wall 10 is selected essentially from material which is permeable to the contents of the package. In addition to absorbing the undesired material, the absorbing agent is selected from material so as to be harmless to foodstuffs when foodstuffs are the contents of the package.

In manufacturing the packaging material of FIGURE 1, an absorbing agent 14, such as pulverized alkali carbonate, is introduced in finely divided form between the inner layer 10 and the outer layer 12 by being dispersed on the surface of the outer layer 12. The layers 10 and 12 may be selected from any one of the heat-sealing therrnoplastic materials such as polyethylene, rubber hydrochloride, polyvinyl chloride, polyester, etc. It is thus apparent that the absorbing agent 14 may be introduced into the packaging material at the time of the manufacture of the packaging material itself; with such an arrangement the absorbing agent does not require any special feeding machine and the filling space of the package remains free of additions or inserts.

It is not necessary that the absorbing agent be dispersed over the entire surface of the sheet as shown in FIGURE 1 but also may be distributed on small areas or strips. As is illustrated in FIGURES 2 and 3, the absorbing agent 24 is dispersed on a rectangular area of the outer layer 22 and is covered by the permeable layer 20. It is apparent that the particular size and shape of the absorbing agent area 24 may be varied in accordance with the final shape of the package. If such a strip of packaging material as shown in FIGURES 2 and 3 is subsequently worked on a packaging machine, the areas 24 could be scanned by photoelectric cells, for example, in order to avoid locating such areas 24 within the closure seams of the package.

FIGURE 4 illustrates a composite sheet including an inner layer 30 permeable to the undesired substance to be removed, an absorbing agent 34 dispersed on a supporting layer 36 and an outer layer 32. The absorbing agent 34 may be applied to the surface of the supporting layer 36 or the layer 36 may be impregnated with the absorbing agent 34; then the supporting layer 36 is merely inserted between the inner and outer layers 30 and 32.

As an example of packaging material manufactured according to the present invention, it is assumed that the package is to be used for roasted cotiee which, as is known, gives off carbon dioxide in the initial period after roasting, as a result of which the package bulges. The

absorbing agent should therefore combine with the carbon dioxide and the inner layer of the packaging material must be permeable to the carbon dioxide. In this instance, the composite sheet shown in FIGURE 4 includes an inner layer 30 made of polyethylene, an absorbing agent 34 of pulverized alkali carbonate dispersed on a supporting layer 36 of aluminum foil, and an outer layer 32 forming the outside of the package.

While the individual layers may be firmly bound to each other, it is also contemplated that the layers may 'be bound together only at certain areas, for instance, at the edges of the packaging material. In such cases, one of the two layer surfaces covering the absorbing agent is provided with an adhesive. Thus, the composite sheet of FIGURE 4 may include an adhesive on the supporting layer 36 to retain the absorbing agent 34 thereon, after which, the unitary agent 34 and layer 36 are inserted between the inner and outer layers 30 and 32.

Inasmuch as the present invention is subject to many other modifications and changes, it is intended that all matter contained in the foregoing description and shown on the accompanying drawing, shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. The method of making packaging material for use in wrapping a commodity in a protective manner so that a deleterious substance is removed from the commodity during its packaged state, which comprises, supplying a first sheet of material having a property of permeability, supplying a second sheet of material, bringing such sheets together into superimposed relation with the first sheet constituting an inner layer and the second sheet constituting an outer layer, sandwiching an absorbing agent between the layers, and fixing the layers in such superimposed relationship with the absorbing agent located therebetween, whereby a deleterious substance in the commodity contained within a package filling space delineated by the inner layer is drawn through the inner layer without structural damage to such layer and is sucked up by the absorbing agent without diminishing the filling space.

2. The method as recited in claim 1, wherein said absorbing agent is in finely divided form and is applied to the outer layer.

3. The method as recited in claim 2, wherein said absorbing agent is applied in a plurality of separate areas to the outer layer.

4. The method as recited in claim 1, wherein said absorbing agent is applied to a supporting layer, after which the supporting layer is inserted between said inner and outer layers.

5. The method as recited in claim 4, wherein said supporting layer is provided with an adhesive to retain said absorbing agent thereon.

6. The method as recited in claim 4, wherein said absorbing agent is impregnated on the supporting layer.

7. The method as recited in claim 1 wherein said inner and outer layers are formed from a heat-sealing thermo plastic material.

8. The method of recited in claim 7 wherein said absorbing agent is pulverized alkali carbonate.

References Cited UNITED STATES PATENTS 2,615,614 10/1952 Linda 16l206 XR 2,648,487 8/1953 Linda 16l206 XR 3,130,647 4/1964 Anderson et al. 156-290 XR 3,140,196 7/1964 Lacy et al 156-244 XR FOREIGN PATENTS 883,069 11/1961 Great Britain.

EARL M. BERGERT, Primary Examiner.

H. F. EPSTEIN, Assistant Examiner.

US. Cl. X.R. 53-4 

